1. Field
The present disclosure relates to antennas and, more specifically but not exclusively, to arrayed antennas for coherent detection of millimeter-wave and terahertz radiation.
2. Description of the Related Art
This section introduces aspects that may help facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
As used herein, the term “millimeter wave” refers to electromagnetic radiation from a range of frequencies between about 30 GHz and about 300 GHz. It has received this name because the corresponding wavelengths are between about 1 mm and about 10 mm. In some literature, this frequency range is also referred to as the EHF (Extremely High Frequency) band. The term “terahertz radiation” refers to electromagnetic radiation from a range of frequencies between about 300 GHz and about 3 THz. Because terahertz radiation includes wavelengths between about 1 mm and about 0.1 mm, it is also referred to as the sub-millimeter waves, especially often so in astronomy.
Practical applications of millimeter waves and terahertz radiation include but are not limited to imaging systems, security scanners, automotive sensors, wireless communications, defense usages, such as radar, and medical applications. The design of corresponding antennas is typically application specific, with integration, loss, gain, and directivity requirements varying significantly among different applications. Some of the applications require or may benefit from the use of a high-gain low-directivity antenna.